1. Technical Field
The present invention relates to a developing device and an image forming apparatus using liquid developer prepared by dispersing toner in carrier liquid.
2. Description of the Related Art
Structures having a tank section storing liquid developer and a primary reservoir section with a partition wall arranged between the tank section and the reservoir section in a developing unit are known.
With such a structure, liquid developer is discharged into the primary reservoir section over the partition wall when the quantity of the liquid developer stored in the tank section for storing liquid developer to be supplied to a developing roller exceeds a predetermined level. The structure has a circulation route such that the liquid developer in the primary reservoir section is subsequently collected into a developer adjusting section and adjusted for concentration before it is returned to the tank section by way of the circulation route.
However, with the technique described in Patent Document 1 (JP-2007-147973A), liquid developer is deposited in the space between a limiting blade and a developer supply roller arranged below the limiting blade by an agitation roller to give rise to a pressure rise relative to the limiting blade and the deposited liquid developer can adversely affect the thickness of the film on the developing roller and consequently put the liquid developer being supplied onto the photosensitive body out of balance to degrade the quality of the formed image.